A Computer On Module or COM is a type of single-board computer. The COM module is a complete computer built on a single circuit board. The design is centered on a single microprocessor with RAM, input or output and all other features needed to be a functional computer on the board. However, unlike a single-board computer, the COM module will usually be deficient in the standard connectors for any input or output peripherals to be attached directly to the board. Instead, the wiring for these peripherals is brought out to pin-headers on the board. The module will usually need to be mounted on a baseboard which has the standard peripheral connectors.

There are different types of Computer on Modules that are used for different purposes and one of the most common functions of a COM is in data communication, they help transfer data faster with the use of RFID Readers and RFID cards. Today they are as well used in the control panels of planes and jets for avionics and medical equipments with the help of a Touch Panel, pilots and doctors can make commands on the equipments faster and with better accuracy. The most recent function of this COM is in transportation with the use of Smart Cards for faster access and processing of transportation services.